Express your answer as a mixed number simplified to lowest terms. $3\dfrac{5}{16}-1\dfrac{9}{12} = {?}$
Simplify each fraction. $= {3\dfrac{5}{16}} - {1\dfrac{3}{4}}$ Find a common denominator for the fractions: $= {3\dfrac{5}{16}}-{1\dfrac{12}{16}}$ Convert ${3\dfrac{5}{16}}$ to ${2 + \dfrac{16}{16} + \dfrac{5}{16}}$ So the problem becomes: ${2\dfrac{21}{16}}-{1\dfrac{12}{16}}$ Separate the whole numbers from the fractional parts: $= {2} + {\dfrac{21}{16}} - {1} - {\dfrac{12}{16}}$ Bring the whole numbers together and the fractions together: $= {2} - {1} + {\dfrac{21}{16}} - {\dfrac{12}{16}}$ Subtract the whole numbers: $=1 + {\dfrac{21}{16}} - {\dfrac{12}{16}}$ Subtract the fractions: $= 1+\dfrac{9}{16}$ Combine the whole and fractional parts into a mixed number: $= 1\dfrac{9}{16}$